Treasure of the month: Humboldt's night bird
9 September 2019
Photo: UHH/CeNak, Stau
The fat swallows from the ornithological collection in the special exhibition "Humboldt Alive!"
Double is better - the treasure of the month September is available twice in the Museum of Nature - Zoology! Steatornis caripensis, or Guácharo in Spanish, translates as fat martin. Since May, one of the two fat swallows can now be seen in the special exhibition "Humboldt lives!" in the Museum of Nature - Zoology. The other one is still resting in our ornithological collection.
How the treasure came to us in the museum
One fatback found its way to us in the Zoological Museum via the Federal Research Institute for Forestry in Reinbek in 1957, the other originates from Colombia. From Cerro Munchique, it was finally sold to the Zoological Museum in Hamburg in 1971 along with another 100 animals, thus strengthening the collection that had been badly damaged during World War II.
The oilbird from Venezuela
On one of his expeditions to what is now Venezuela, locals led Alexander von Humboldt into a dark cave and showed him a bird they had long known: the oilbird. Thus, in 1817, Humboldt described the bird species in detail for the first time and classified it scientifically. The fat martin owes its less charming sounding name to the fatty fruits on which it feeds. It is often referred to as the oilbird, because of its high fat content, the locals cooked it and used the fat to make oil or butter.
Orientation by echolocation
Shrieking, growling and clicking - the fat martin not only orients itself by sight, but also emits clicking sounds, which in turn return an echo - similar to a bat. However, the clicking sounds of the fat martin are audible to us humans. It uses this technique mainly in the dark resting and breeding burrows where it is too dark to see anything.
Thus, it is also considered probably the loudest bird in the world. Even Humboldt reported from one of his expeditions: "It is difficult to get an idea of the terrible noise that thousands of these birds make in the dark interior of the cave."
The chicken of the South American caves
Males and females do not differ externally; both have reddish-brown plumage with white spots, making them well adapted to their environment. At 40 to 50 centimeters in size, the fat martin is about the size of a chicken, but far lighter.
While active at night to gather fruit, the fat martin hides in the dark caves of South America during the day. It is the only nocturnal, flying, fruit-eating bird in the world that also has a keen sense of smell. The fat martin nests in cliffs and the recesses of dark caves. Although some parts of its habitat are already protected, deforestation and climate change may soon threaten the species.
More information
Special exhibition
Ornithology